The xDSL is a high-speed data transmission technology for transmitting data in telephone twisted-pairs. With the increase of a frequency band used by the xDSL, the crosstalk problem at a high frequency band becomes more prominent. When multiple subscribers need to launch an xDSL service in a bundle of cables, due to the crosstalk problem, rates of some lines become lower, performance of them becomes unstable, and sometimes the service even cannot be launched. As a result, a Digital Subscriber Line Access Multiplexer (DSLAM) has a low line activation rate. Multiple twisted-pairs are present on the cables of the subscribers, and various services may run on each twisted-pair. When various types of xDSLs work simultaneously, crosstalk is generated between the lines, and the performance of some lines drops sharply due to the crosstalk problem. When lengths of the lines are relatively great, the lines of some twisted-pairs cannot launch any forms of DSL services at all coordinated transceiver
In the prior art, coordinated transmission and reception are performed by using a precoder or canceller at a DSLAM end, and crosstalk is cancelled by using a signal processing method, so that crosstalk in each path of signal is eventually reduced. However, the existing precoder or canceller has great interference on an adjacent subscriber during a training procedure, and even leads to call drops of other subscribers when the interference is serious.